And in this respect, said Dr. Barry Farr, professor emeritus of medicine at the University of Virginia, screening measures to detect the bug play an integral role.
"Based upon available scientific data, isolation of all colonized and infected patients was the highest rated control measure recommended by the CDC's 2006 guideline, and no other control measure comes close to having so much data documenting success," Farr said, adding that such isolation can only take place if patients who are infected with MRSA are identified early.
But other doctors said the new finding suggests that many hospitals may have been too quick to implement an additional, largely unproven admissions procedure that turned out to have a minimal role in controlling the spread of MRSA.
"Some people advocated 'catching the bug early … to reduce its spread,'" said Dr. Marvin Bittner, associate professor at the Creighton University School of Medicine in Omaha, referring to the new study. But he added that this was a controversial measure at best, and one that was not generally supported by the CDC.
"In my opinion, the decisions to screen patients for MRSA were political decisions and not medical decisions," agreed Clyde Thornsberry, chief scientific advisor for anti-infective services for Eurofins Medinet Inc. of Herndon, Va.
"My guess is that most infectious disease physicians and microbiologists would have predicted that the return would have been minimal."
Still, even lead author Harbarth said MRSA screening may have its place in hospitals — particularly when it comes to certain patients or populations that may be particularly vulnerable to the bacteria.
The study, Harbarth said, focused on "MRSA rates only in surgery, only in one hospital in Switzerland.
"Screening may still be useful in intensive care units or in hospitals with high infection rates, so there's a little word of caution."